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Solar chargers don't work under ESS

Good day,

Two solar chargers Smart MPPT 150/70-Tr and Smart MPPT 250/70-Tr don't charge the batteries under ESS mode. On VRM the system shows this:


I have set the system to not sell any PV excess to grid. However if I set the system to sell the excess, controllers do start to charge and export PV excess to grid:


Moreover, if we disconnect the VE.Direct cable from both controllers to Venus GX, they do charge battery bank but system doesn't run under ESS:


Any clue of what could be wrong on configuration? I need to set the system up properly for ESS and I have compared all parameters with other systems I have installed that seems to run properly on ESS.

Thank you in advance for your help.

dgmar-ni asked
dgmar-ni commented ·

1 Answer

Multiplus compact version, smartsolar and ESS

Hi, this is what I would like to achieve, see picture also with schematics.

Daytime (green arrows):

- Run load on solar - power from MPPT through inverter to load

- Charge battery on the leftover solar current (split solar charge current to inverter and battery, is the split configurable in some way?)

Nighttime (orange arrow):

- Run load from battery through inverter

- If battery SOC is too low use grid power (light blue arrow from grid through Multiplus)

Equipment I already have:

- Multiplus Compact - mfd. 2013

- Smartsolar 150/60 MPPT - mfd. 2021

- Solarcells and battery

The question is can I create this configuration with the multiplus compact I have if I purchase the Cerbo GX controller? I also read something about gen2 processor on multis needed and some firmware version limitiations. But I could not get the grips of it. So I try to ask here:

1. what should I check with my multi compact to be sure I get this to work as I plan.

2. And can this be done with the cerbo GX and a multi compact?



norrback asked
alexcj commented ·

4 Answers

ESS System not feeding in grid :-(

I got a 5k MultiPlus II running with a set of 10kWh BYD LiFePo4 batteries (with their own BYD BMS) en two DC-connected MPPT's with a total PV-capacity of around 2400Wp and a Cerbo "running things"..
The Cerbo is updated to the latest firmware (automagically through the internet). The MultiPlus II is on firmware 2623470 and runs the ESS-assistant more or less with the default values of the German gridcode with internal NS protection.
The only thing I didn't let the assistant change, is the type of battery (because of the BYD-specific settings for Absorption and Float).
This time of year I have quite a surplus of PV-energy so I started experimenting with ESS (Optimized with BatteryLife).
For some reason the system is NOT feeding the surplus of PV back to the grid :-(
Only if I set the grid setpoint to a negative value, the system starts to feed back the PV to the grid at the height I set the negative grid setpoint to....
Otherwise, the BMS (I think) switches off the MPPT's so they don't deliver any PV anymore :-(
For some reason it does that when the BMS says (at VRM and in Remote Console) that the batteries are at 99% instead of 100%. I have no idea why it does that but this doesn't bother me too much ;-).
I set the minimum SOC (unless grid fails) at 95% otherwise apparently the system thinks it should feed the loads from the grid, even when there's still enough PV to do that and even enough to charge the batteries.
So not the actual surplus of PV energy is fed into the grid, but the value set with the negative grid setpoint...
So when there's a cloud before the sun and the batteries are still above the minimum SOC (unless grid fails) then the system feeds the grid from the batteries if the PV drops below the value set in the negative grid setpoint....
I probably have some setting "wrong" to get this result, but I can't seem to think of what could be wrong....
If someone has suggestions..... they are more then welcome.

spithost asked
marekp commented ·

8 Answers

Slow battery charging

I work in a hospital in Mulanje (Malawi). We have recently connected 6 Quattro (6x15kW) with 6 Fronius Symo (6x15kW) AC-coupled. We have 6 battery banks (29 batteries in total). Each bank has a BMV and battery capacity of 500Ah (5x100Ah). 1 bank is different with 400Ah (4x100Ah). It is in Malawi not allowed to feed back to the grid. The system is running pretty good but we are dealing with the next issue.

When there is not enough solarpower to provide the load of the hospital and to charge the batteries the system is not using the grid to charge the batteries. For example we have a powercut and the batteries will be discharged until 8% and the powercut is over it will not start charging the batteries from the grid to the minimum SOC set in the ESS. Also not when i enable the setting 'keep battery charged'. Only when there is enough solarpower it will use the batteries to store the load. what can i do to change this? See pictures for more info. Thanks in advance.



mmh asked
marekp edited ·

3 Answers

ESS VE Config query when using current sensor instead of grid meter.

Hi All,

Quick question on VE Config setting.

Set Up - Parallel grid tied AC ESS, Multiplus II, Venus OS (pi4), 30m external Current Sensor connected directly to the Multi, existing PV with grid tied 'dumb' inverter using victron AC current sensor, (NO power meters).

Question1 - In VE Configure General Tab - 'External current sensor connected' - should this be ticked ? -

Question2 - Now in the ESS settings on the VRM portal after loading the assistants what do we select under 'Control without grid meter' - On or Off ? We have no grid meter as we are using the current sensor, however its a parallel system so the house loads are not installed on the AC out as stated in the ESS manual ?

Thanks for taking the time to read this and any help you are able to offer.

jetstram61 asked

0 Answers

High frequency issue when grid fails

I work in a hospital in Mulanje (Malawi). We have recently connected 6 Quattro (6x15kW) with 6 Fronius Symo (6x15kW) AC-coupled. We have 6 battery banks (29 batteries in total). Each bank has a BMV and battery capacity of 500Ah (5x100Ah). 1 bank is different with 400Ah (4x100Ah). It is in Malawi not allowed to feed back to the grid. The system is running pretty good but we are dealing with one issue.

When we have low voltage (<180v) the Victron will switch from grid to the battery. Then the frequency goes up briefly to 52,9Hz or 53,1Hz. The next thing is that the Fronius-inverters shut down because of high frequency (error state 105). We have the correct county-settings in the Fronius (MG50). I know that it happens when there is no place to store the energy. But it happens also when the battery is at 40% and the hospital load is 40-60kW. The Fronius-inverters try to start up again and again but gives error until the grid-voltage is good enough for the Victron to go back to the grid. Normally it happens, between 11-2, when the sun is very strong and we need the Fronius-inverters to charge the batteries for the night. In the ESS is the possibility to change the frequency range but the advice to leave it like it is. I added some pictures for clarification. What can we do to solve this issue?

Thanks in advance, Gerwin Habermehl




mmh asked
mmh commented ·

1 Answer

RCD placement in Multi-II ESS

Hi - on a 3x MPII 5000 ESS system, Victron requests a RCD Type A on AC-Out-1. We have realized that with a 4phase RCD 300mA. Does this RCD need to sit immediately at the AC out or can there be a distribution block in-between?

Background: we have a thick cable running back from the installation in the garage to the house, so the AC Out RCD is in line with the then following house connection. However, between AC Out and RCD in the garage, we have a block connecting AC out with solar inverter AC, wallbox (with separate 30mA RCD), some plugs (with separate 30mA RCD).

Any trouble/disadvantage with such an arrangement?

krouink asked

0 Answers

On-Grid PV Inverter als Generator für Multiplus II ?


ich möchte ein AC-ESS mit einem Multiplus II 5000, Pylontech-Akkus und dem EM24 realisieren. Als PV Anlage habe ich noch eine Anlage von 2010 im "Überschussmodus".

Soweit, so gut. Leider habe ich aber keine Autarkie-Möglichkeit, sollte das öffentliche Netz mal down sein. Ich habe dann lediglich die Akku-Ladung da sich mein Wechselrichter (Mastervolt XS4300) nicht mit dem Multiplus AC-koppeln lässt.

Nun aber folgender Gedanke: am Multiplus stelle ich AC In1 auf "Generator" und schließe dort den PV-Wechselrichter an. Dieser synct mit dem Multiplus und lädt dadurch primär den Akku.

Start/Stop des PV-Inverters ließe sich über den Relaiskontakt schalten, wenn der Akku voll ist, wird ein Relais geschaltet und der Wechselrichter vom Multiplus getrennt, wird eine bestimmte Akkuladung unterschritten, dann wird der Wechselrichter hinzugeschaltet, synchronisiert und lädt dann den Akku.

Das wäre vielleicht nicht die eleganteste Lösung, sie soll ja aber auch nur im Desasterfall funktionieren.

Wäre das prinzipiell möglich oder habe ich einen Denkfehler?
Besten Dank!

chrisu asked
chrisu answered ·

9 Answers

Data Showing incorrectly - 3 Phase Grid, 3 Phase PV (Enphase), 1 Phase ESS (MultiPlus-II)

We are using two ET340 Meters, one for the incoming Grid and one for the PV.

The calculations of AC Loads and Critical Loads are very obviously wrong.

Basic Drawing:


Tests Done:

With no PV


With just L1 Enphase inverters on:


With all 3 phases on:


If we change the Meter programming to AC Input (intentionally wrong but just testing):



Incorrect load showing on critical (as expected because the PV is physically on the AC output.)

It seems that the loads are being calculated wrong. L2 and L3 are showing critical load when there is no MultiPlus on there phases and the total calculated plus the grid export is higher than the Production by nearly double.

Try turning “Inverter AC output in use” which removed the Critical load calculation and the AC Load calculation still reads wrong values.



Anything else we can try?

ben-stanton asked
ben-stanton commented ·

1 Answer

Help to understand ESS and home grid plug

I Will make an ES


S system with a Esaysolar II GX 24/3000/70.I have the grid in my house.

I could not find schematic about how to wire my home system with the multiplus. I read that the main grid have to connect to the AC-in. And to AC-out the critical load. But I don't understand because I have only one grid in my house? Should I plug the same wire AC-IN with AC-Out So when the grid fall down AC-OUT power my house?

nimrod asked
seb71 commented ·

4 Answers

Multiplus: I don't want to use battery power on AC2 dump load

I have a MultiPlus II 8000, MPPT RS450/100 and 18 x 370w solar panels. I have a 8kw lithium battery bank. I am not allowed to feed into the grid. I don't have a ET112 energy meter installed currently. My whole DB board goes through the system. Critical loads on AC1 and 2 geysers and a small stove on AC2. I live in SA and we have blackouts twice daily for 2 hours Which uses about 30% of my battery bank (maximum).

When the geyser and stove switches on the solar power is usually sufficient but sometimes there is a shortfall and is supplemented by the battery instead of the grid. What are my options here?

1) Is there a way to program ESS / another assistant to ensure that the battery is not used for AC2 loads?

2) Do I need to take these loads off the AC2 and bypass the system and then use the ET112 Energy Meter to power these extra loads with excess solar power and grid only.

A best practice and long term solution answer will be appreciated. Thanks.

jond asked
lifeingalicia answered ·

2 Answers

Stuck on Float Voltage in ESS

After monitoring VRM since installing ESS I've noticed that my Bat and Charging voltage never reaches absorption voltages. My absorption volage is 57.6v, Float is 54.4v (AGM) as configured on the Multi. In ESS, SOC is 85% (Min and actual.) I also have two scheduled charges. One charge begins at the tail-end of usable PV late in the day, overlapping the last bit of sun (to capture some PV so as to limit some of the draw from the grid when charging.) This charge ends roughly 6 hrs later around 1:00 AM EST at which point I am inverting for 6 hrs, until the sun comes up. Both scheduled charges have SOC limit reached unchecked so that it stays in the charging cycle, intentionally, to keep the Multi from slipping back into inverting.

Other ESS settings that might be pertinent, Optimized Mode with Battery Life, DC-Coupled Feed-in with Limit 0W.

Even during the scheduled charges, mostly grid supplied, I never see more than the float voltage. Any thoughts as to what or why this is? @Alexandra perhaps you can comment as you are very knowledgeable on this area? :)

duswami asked
duswami commented ·

4 Answers

Whats the best way to see activity on L2 using ESS

I'm running a DC coupled ESS system (mode 1). My panel is split phase not 3 phase. I have essential loads on AC out 1 Connected to L1 in the breaker panel (120v). I am not currently using AC out 2 for non essential loads they are still in the breaker panel. Aside from moving those loads to AC out 2, What alternative do I have to to monitor L2 in VRM and have ESS take it into consideration? I do have an EM24 That is not hooked up to the system. But if I use it it supersedes the current monitoring of the multiplus plus, that is my understanding. Any suggestions?

duswami asked
duswami answered ·

4 Answers

Full batteries -> Switch to absorption -> Voltage Spike -> DC Ripple shutdown

I'm running a Multiplus-II 2x120, SmartSolar MPPT, Cerbo GX, and a new pair of Ampere Time 200Ah batteries with built-in BMS. I had been running three 100Ah Battle Born batteries before and saw something similar.

Today is the second day with the new batteries, so I specifically set the ESS parameters to fully charge the batteries. Exactly as the batteries reached the default absorption voltage of 14.2, the system "crashed" flashing the Overload and Low Battery LEDs. This happened yesterday morning as well when I was first starting the system after the batteries were fully charged using an external charger. I should add that there has been abundant sunshine and solar power both days and the SmartSolar was delivering significant power.

My theory is the batteries reach the threshold to switch into absorption and the system -- not sure which part -- creates a brief voltage spike (I've seen it over 15 volts using a meter) when switching into absorption. The battery's built-in BMS detects the excess voltage and disconnects resulting in 1) the low voltage warning in the log (resolved in 3 seconds) followed by 2) the DC ripple shutdown.

My question, assuming the system voltage spike is indeed the primary cause of and can't be eliminated, is how best to prevent this in the future. I'm running an ESS Mode 2 program, so I can program the system to not fully charge the batteries, but it just seems like there should be a better solution.




jm0278 asked
trevor-bird commented ·

4 Answers

Lasten AC-Out(Kritische Lasten) zeigt nichts an.


Ich habe gerade meinen Multiplus 2 in betrieb genommen.
Konfiguriert ist er als ESS. AC in an Hausanschluss L1 und als Energiemeter läuft ein EM24 Ethernet.

An AC-out1 habe ich Werkstatt/zwei Vorhandene Wechselrichter 3000W angeschlossen.
Aktuell werden ca 200W Produziert.

In der Remote Konsole werden mir bei Kritischen Lasten immer 0W angezeigt. Ich hatte die Hoffnung das mir hier der Aktuelle Wert der an AC-Out1 verbraucht oder Produziert wird angezeigt wird.

Habe ich da ein Denkfehler oder ist es gar nicht Möglich?



der-neue asked
sun-pwr42 commented ·

6 Answers

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